JP6766250B2 - Elastic wave device, duplexer and communication device - Google Patents

Description

The present disclosure relates to an elastic wave device which is an electronic component using an elastic wave, a demultiplexer including the elastic wave device, and a communication device. The surface acoustic wave is, for example, a surface acoustic wave (SAW).

As an elastic wave device, a so-called WLP (wafer level package) type device is known. The WLP-type elastic wave device has, for example, a piezoelectric substrate, an excitation electrode located on the upper surface of the piezoelectric substrate, and a cover that covers the upper surface of the piezoelectric substrate from above the excitation electrode and seals the excitation electrode. .. The cover is formed so as to form a space on the excitation electrode, for example, so that elastic waves can easily propagate on the upper surface of the piezoelectric substrate (so that the piezoelectric substrate easily vibrates).

In the above configuration, there is known a technique of providing a reinforcing layer made of a conductor (metal) on the upper surface side of the cover in order to prevent the cover from bending toward the space side (for example, Patent Documents 1 to 3). ). Patent Document 1 discloses a reinforcing layer having a striped or mesh-like planar shape.

Japanese Unexamined Patent Publication No. 2008-227748 Japanese Patent No. 4586852 Japanese Unexamined Patent Publication No. 2011-188255

The elastic wave device according to one aspect of the present disclosure includes a piezoelectric substrate, a support substrate having a smaller thermal expansion coefficient than the piezoelectric substrate located on the lower surface of the piezoelectric substrate, and an excitation electrode located on the piezoelectric substrate. A cover forming a space on the excitation electrode and a plurality of first strip conductors extending in parallel with each other on the cover and at least partially overlapping the space in plan perspective. ing.

The demultiplexer according to one aspect of the present disclosure includes a transmission filter that filters a transmission signal and outputs it to an antenna, and a reception filter that filters a reception signal from the antenna. At least a part of the receiving filter is included in the elastic wave device described above.

The communication device according to one aspect of the present disclosure includes an antenna, the demultiplexer connected to the antenna, and an IC connected to the demultiplexer.

It is an external perspective view which shows the SAW apparatus which concerns on 1st Embodiment. It is a perspective view which shows by breaking a part of the SAW apparatus of FIG. It is a top view which shows the structure of the SAW resonator included in the SAW apparatus of FIG. FIG. 4A is a cross-sectional view taken along the line IVa-IVa of FIG. 1, and FIG. 4B is an enlarged view of region IVb of FIG. 4A. It is a top view of the SAW apparatus of FIG. 6 (a) is a perspective view showing an example of the position of the strip conductor relative to the IDT electrode, FIG. 6 (b) is a plan view showing a modified example of the strip conductor, and FIG. 6 (c) is FIG. It is sectional drawing in the VIc-VIc line of. It is a top view which shows the structure of the SAW apparatus which concerns on 2nd Embodiment. It is a top view which shows the structure of the SAW apparatus which concerns on 3rd Embodiment. It is a circuit diagram which shows typically the structure of the demultiplexer configured by a SAW apparatus. It is a schematic diagram which shows the communication device as the use example of a duplexer. 11 (a) and 11 (b) are diagrams showing changes in characteristics due to temperature changes in the SAW apparatus according to Examples and Comparative Examples. It is a figure which shows the change of the characteristic by the temperature change in the SAW apparatus which concerns on another Example and comparative example. It is a partial sectional view of the SAW apparatus which concerns on a modification. It is a top view which shows the structure of the SAW apparatus which concerns on 4th Embodiment. It is sectional drawing which shows the modification of the through conductor.

Hereinafter, embodiments according to the present disclosure will be described with reference to the drawings. The figures used in the following description are schematic, and the dimensional ratios and the like on the drawings do not always match the actual ones.

For the same or similar configurations, different alphabetic symbols may be added to the symbols of the same name and the same number, such as "terminal 9A" and "terminal 9B", and in this case, simply The alphabet may be omitted, as in "terminal 9".

In the second and subsequent embodiments, with respect to the configuration common to or similar to the configuration already described, the reference numerals attached to the configurations already described may be used, and illustration and description may be omitted. It should be noted that the configurations corresponding to (similar to) the configurations already described are the same as the configurations already described, except that there is no particular notice even when the configurations are different from the configurations already described.

The SAW apparatus according to the present disclosure may be in any direction upward or downward, but in the following, for convenience, an orthogonal coordinate system including D1 axis, D2 axis and D3 axis is defined, and an orthogonal coordinate system is defined. Terms such as upper surface and lower surface may be used with the positive side of the D3 axis facing upward. Further, the term "planar view" or "planar perspective" means viewing in the D3 axis direction unless otherwise specified. The D1 axis is defined to be parallel to the propagation direction of SAW propagating along the upper surface of the piezoelectric substrate described later, and the D2 axis is defined to be parallel to the upper surface of the piezoelectric substrate and orthogonal to the D1 axis. , D3 axis is defined to be orthogonal to the upper surface of the piezoelectric substrate.

<First Embodiment>
(Overall configuration of SAW device)
FIG. 1 is an external perspective view showing the configuration of the SAW device 1 according to the first embodiment. FIG. 2 is a perspective view showing a part of the SAW device 1 broken.

The SAW device 1 is a WLP-type electronic component, and its outer shape is, for example, a substantially thin rectangular parallelepiped shape. The dimensions of the SAW device 1 may be set as appropriate. As an example, the length of one side (D1 axis direction or D2 axis direction) in plan view is 0.3 mm or more and 2 mm or less, and the thickness (D3 axis direction) is 0.2 mm or more and 0.6 mm or less. Is.

A plurality of terminals 9A to 9K (12 in the illustrated example) are exposed on the upper surface of the SAW device 1. The SAW device 1 is mounted on the circuit board, for example, by arranging the upper surface of the SAW device 1 so as to face a circuit board (not shown) and joining the pads of the circuit board and the terminals 9 with bumps such as solder. After that, a mold resin (not shown) is arranged around the SAW device 1 by a transfer mold or the like, and the SAW device 1 is resin-sealed. The mold resin is also filled in the gap formed between the circuit board and the SAW device 1 by the thickness of the bump.

The SAW device 1 includes, for example, a substrate 3, one or more SAW resonators 5 (plural in the illustrated example) provided on the upper surface of the substrate 3, a cover 7 covering the SAW resonator 5, and a cover 7. It has the above-mentioned plurality of terminals 9 exposed on the upper surface 7a of the cover 7 and a reinforcing layer 11 overlapping the upper surface 7a of the cover 7.

The substrate 3 has, for example, a piezoelectric substrate 13 and a support substrate 15 attached to the lower surface of the piezoelectric substrate 13.

The piezoelectric substrate 13 is made of, for example, a single crystal having piezoelectricity. The single crystal comprises, for example, lithium tantalate (LiTaO ₃ ), lithium niobate (LiNbO ₃ ) or quartz (SiO ₂ ). The cut angle may be appropriate. For example, the piezoelectric substrate 13 is for rotating Y-cut X propagation. That is, the X-axis is parallel to the upper surface (D1 axis) of the piezoelectric substrate 13, and the Y-axis is inclined at a predetermined angle with respect to the normal of the upper surface of the piezoelectric substrate 13.

The planar shape of the piezoelectric substrate 13 is, for example, a rectangle. The size of the piezoelectric substrate 13 may be appropriately set. As an example, the length of one side (D1 axis direction or D2 axis direction) in plan view is 0.3 mm or more and 2 mm or less, and the thickness (D3 axis direction) is 0.1 μm or more and 30 μm or less. .. The thickness may be defined by the wavelength of the SAW excited by the SAW resonator 5, and in that case, it may be 0.05λ or more and 15λ or less. For example, when the SAW device 1 functions as a 2 GHz filter, 1λ is about 2 μm.

The support substrate 15 is formed of, for example, a material having a coefficient of thermal expansion smaller than that of the material of the piezoelectric substrate 13. Thereby, for example, the temperature change of the electrical characteristics of the SAW device 1 can be reduced without promoting the thermal expansion of the piezoelectric substrate 13. In particular, when the piezoelectric substrate 13 and the support substrate 15 are directly bonded or are bonded via an intervening layer of 15λ or less, the support substrate 15 suppresses thermal deformation of the piezoelectric substrate 13 and causes the SAW apparatus 1. It is possible to reduce the temperature change of the electrical characteristics. Examples of such a material include semiconductors such as silicon, single crystals such as sapphire, and ceramics such as aluminum oxide sintered bodies. The support substrate 15 may be configured by laminating a plurality of layers made of different materials.

The plan shape and the dimensions of the support substrate 15 in a plan view are, for example, the same as those of the piezoelectric substrate 13. The thickness of the support substrate 15 may be appropriately set. For example, the thickness of the support substrate 15 is made thicker than the thickness of the piezoelectric substrate 13. As an example, the thickness of the support substrate 15 is 10 times or more the thickness of the piezoelectric substrate 13, and is, for example, 100 μm or more and 300 μm or less.

The piezoelectric substrate 13 and the support substrate 15 are attached to each other, for example, via an interposition layer (not shown). The material of the interposition layer may be an organic material or an inorganic material. Examples of the organic material include resins such as thermosetting resins. Examples of the inorganic material include SiO ₂ , Si ₃ N ₄ , Al N and the like. Further, a laminated body in which thin layers made of a plurality of different materials are laminated may be used as an intervening layer. As such a laminated body, for example, an acoustic reflection film may be formed. Further, the piezoelectric substrate 13 and the support substrate 15 may be bonded by so-called direct bonding, in which the bonding surface is activated by plasma, neutron rays, or the like and then bonded without an intervening layer.

The SAW resonator 5 is configured by providing a conductive layer or the like on the upper surface 13a of the piezoelectric substrate 13. The plurality of SAW resonators 5 may be connected to a ladder type, for example, to form a ladder type SAW resonator filter. Further, by providing two or more such filters, the plurality of SAW resonators 5 (SAW apparatus 1) may form a duplexer (for example, a duplexer).

In the description of the present embodiment, when the function of the terminal 9 and the like are described, the case where the SAW device 1 is a demultiplexer may be taken as an example.

The cover 7 has, for example, a frame-shaped frame portion 17 in a plan view and a lid portion 19 that closes the opening of the frame portion 17. As a result, a space 21 (FIG. 2) for facilitating the vibration of the upper surface 13a is formed on the upper surface 13a of the piezoelectric substrate 13.

The frame portion 17 is formed, for example, by forming one or more openings serving as a space 21 in a layer having a substantially constant thickness. The thickness of the frame portion 17 (height of the space 21) is, for example, several μm to 30 μm. The lid portion 19 is composed of, for example, layers having a substantially constant thickness laminated on the frame portion 17. The thickness of the lid portion 19 is, for example, several μm to 30 μm.

The frame portion 17 and the lid portion 19 may be made of the same material or may be made of different materials. In FIGS. 1 and 2, the boundary line between the frame portion 17 and the lid portion 19 is clearly shown for convenience of explanation, but in an actual product, the frame portion 17 and the lid portion 19 are integrally made of the same material. It may be formed in.

The cover 7 (frame portion 17 and lid portion 19) is basically composed of an insulating material. The insulating material is, for example, a photosensitive resin. The photosensitive resin is, for example, a urethane acrylate-based, polyester acrylate-based, or epoxy acrylate-based resin that is cured by radical polymerization of an acrylic group, a methacrylic group, or the like. A conductor may be arranged on a part of the cover 7. The coefficient of thermal expansion of the cover 7 may have an appropriate size, and is, for example, larger than the coefficient of thermal expansion of the material of the piezoelectric material constituting the piezoelectric substrate 13.

The terminal 9 is made of, for example, a layered conductor (for example, metal) located on the upper surface 7a of the cover 7. The metal is, for example, Cu. The terminal 9 may be composed of a plurality of conductor layers (a plurality of materials). The planar shape of the terminal 9 may be appropriately set, and is circular in the illustrated example. The terminal 9 is electrically connected to the SAW resonator 5, for example, as will be described later. The number and arrangement of the plurality of terminals 9 may be appropriately set. In the illustrated example, the plurality of terminals 9 are arranged along the outer peripheral edge of the rectangular cover 7 (piezoelectric substrate 13) in a plan view.

The roles of terminals 9A to 9L may be appropriately set. For example, terminals 9C, 9G and 9K are terminals used for signal input or output, and other terminals 9 (9A, 9B, 9D, 9F, 9H, 9I, 9J and 9L) are provided with a reference potential. It is a terminal to be used. When the SAW device 1 is a demultiplexer, for example, the terminal 9C is an antenna terminal connected to an antenna, and one of the terminals 9G and 9K receives a transmission signal to be output from the antenna terminal (9C). The other is a receiving terminal that outputs a received signal input from the antenna terminal.

The material of the reinforcing layer 11 is, for example, a material having a higher Young's modulus than the material of the cover 7, and is, for example, a metal (conductor). The metal is, for example, Cu and may be the same material as the terminal 9 (most of it). Further, the reinforcing layer 11 may be composed of a plurality of conductor layers (plurality of materials). The conductor (material of the reinforcing layer 11, metal) generally has a larger coefficient of thermal expansion than the material of the piezoelectric material constituting the piezoelectric substrate 13. The material of the reinforcing layer 11 and the material of the cover 7 may have a larger coefficient of thermal expansion than the other. The thickness of the reinforcing layer 11 may be appropriately set, and is, for example, 20 μm or more and 30 μm or less.

(Basic configuration of SAW resonator)
FIG. 3 is a plan view showing the configuration of the SAW resonator 5.

The SAW resonator 5 is composed of a so-called 1-port SAW resonator. The SAW resonator 5 resonates when an electric signal having a predetermined frequency is input from one of the pads 39A and 39B conceptually and schematically shown, and the signal that causes the resonance is transmitted to the other of the pads 39A and 39B. Output from.

The SAW resonator 5 includes, for example, the above-mentioned piezoelectric substrate 13, an IDT (interdigital transducer) electrode 23 provided on the upper surface 13a of the piezoelectric substrate 13, and a pair of transducers 25 located on both sides of the IDT electrode 23. Includes.

The IDT electrode 23 and the reflector 25 are composed of a layered conductor provided on the piezoelectric substrate 13. The IDT electrode 23 and the reflector 25 are made of, for example, the same material and thickness as each other. The layered conductors constituting these are, for example, metals. The metal is, for example, Al or an alloy containing Al as a main component (Al alloy). The Al alloy is, for example, an Al—Cu alloy. The layered conductor may be composed of a plurality of metal layers. The thickness of the layered conductor is appropriately set according to the electrical characteristics required for the SAW resonator 5. As an example, the thickness of the layered conductor is 50 nm to 600 nm.

The IDT electrode 23 includes a pair of comb tooth electrodes 27. In order to improve visibility, one of the comb tooth electrodes 27 is hatched. Each comb tooth electrode 27 includes a bus bar 29, a plurality of electrode fingers 31 extending in parallel with each other from the bus bar 29, and a dummy electrode 33 protruding from the bus bar 29 between the plurality of electrode fingers 31. The pair of comb tooth electrodes 27 are arranged so that a plurality of electrode fingers 31 mesh with each other (intersect).

The bus bar 29 is formed, for example, in an elongated shape having a substantially constant width and extending linearly in the SAW propagation direction (D1 axis direction). The pair of bus bars 29 face each other in a direction orthogonal to the SAW propagation direction (D2 axis direction). The width of the bus bar 29 may change or may be inclined with respect to the SAW propagation direction.

Each electrode finger 31 is formed, for example, in a long shape extending linearly in a direction (D2 axis direction) orthogonal to the propagation direction of SAW with a substantially constant width. In each comb tooth electrode 27, a plurality of electrode fingers 31 are arranged in the propagation direction of the SAW. Further, the plurality of electrode fingers 31 of one comb tooth electrode 27 and the plurality of electrode fingers 31 of the other comb tooth electrode 27 are basically arranged alternately.

The pitch p of the plurality of electrode fingers 31 (for example, the distance between the centers of the two electrode fingers 31 adjacent to each other) is basically constant in the IDT electrode 23. A part of the IDT electrode 23 may be provided with a narrow pitch portion having a narrower pitch p than most of the others, or a wide pitch portion having a wider pitch p than most of the others.

The number of electrode fingers 31 may be appropriately set according to the electrical characteristics required for the SAW resonator 5. Since FIG. 2 is a schematic diagram, the number of electrode fingers 31 is shown to be small. In practice, more electrode fingers 31 may be arranged than shown. The same applies to the strip electrode 37 of the reflector 25 described later.

The lengths of the plurality of electrode fingers 31 are, for example, equal to each other. The IDT electrode 23 may be subjected to so-called apodization in which the lengths of the plurality of electrode fingers 31 (intersection width from another viewpoint) change according to the position in the propagation direction. The length and width of the electrode finger 31 may be appropriately set according to the required electrical characteristics and the like.

The dummy electrode 33 projects, for example, with a substantially constant width in a direction orthogonal to the SAW propagation direction. The width is equivalent to, for example, the width of the electrode finger 31. Further, the plurality of dummy electrodes 33 are arranged at the same pitch as the plurality of electrode fingers 31, and the tip of the dummy electrode 33 of one comb tooth electrode 27 is the tip of the electrode finger 31 of the other comb tooth electrode 27. And are facing each other through a gap. The IDT electrode 23 may not include the dummy electrode 33.

The pair of reflectors 25 are located on both sides of the plurality of IDT electrodes 23 in the SAW propagation direction. Each reflector 25 may be electrically suspended or a reference potential may be applied. Each reflector 25 is formed in a grid pattern, for example. That is, the reflector 25 includes a pair of bus bars 35 facing each other and a plurality of strip electrodes 37 extending between the pair of bus bars 35. The pitch of the plurality of strip electrodes 37 and the pitch of the electrode fingers 31 adjacent to each other and the strip electrodes 37 are basically the same as the pitch of the plurality of electrode fingers 31.

Although not particularly shown, the upper surface 13a of the piezoelectric substrate 13 may be covered with a protective film made of SiO ₂ or Si ₃ N ₄ or the like from above the IDT electrode 23 and the reflector 25. The protective film may be a multi-layered laminate made of these materials. The protective film may simply be for suppressing corrosion of the IDT electrode 23 or the like, or may be one that contributes to temperature compensation. Further, when a protective film is provided, an additional film made of an insulator or a metal may be provided on the upper surface or the lower surface of the IDT electrode 23 and the reflector 25 in order to improve the reflectance coefficient of SAW.

When the protective film is provided, the protective film may or may not be interposed between the piezoelectric substrate 13 and the frame portion 17. That is, the cover 7 may be placed directly on the upper surface 13a of the piezoelectric substrate 13, or may be placed indirectly.

By applying a voltage to the upper surface 13a of the piezoelectric substrate 13 by one comb tooth electrode 27, the SAW propagating in the D1 axial direction on the upper surface 13a is excited. In the SAW resonator 5, the resonance frequency is substantially the same as the frequency of the SAW having the pitch p of the electrode finger 31 as a half wavelength. The antiresonance frequency is determined by the resonance frequency and the capacitance ratio, and the capacitance ratio is mainly defined by the piezoelectric substrate 13 and is adjusted by the number of electrode fingers 31, the crossing width, the film thickness, and the like.

(Connection between terminal and SAW resonator)
FIG. 4A is a cross-sectional view taken along the line IVa-IVa of FIG. FIG. 4B is an enlarged view of region IVb of FIG. 4A.

As described above, the terminal 9 is electrically connected to the SAW resonator 5 (IDT electrode 23). More specifically, for example, as shown in FIGS. 2 and 4A, a part of the plurality of terminals 9 (for example, 9A and 9K) is a SAW resonator by the wiring 41, the pad 43, and the through conductor 45. It is connected to 5.

The wiring 41 and the pad 43 are configured by, for example, providing a conductor layer on the upper surface 13a of the piezoelectric substrate 13. The conductor may be composed of a conductor layer having the same material and thickness as the conductor layer constituting the IDT electrode 23 and the reflector 25. The pad 43 may include a conductor layer made of another material on a conductor layer common to other parts. The wiring 41 connects, for example, the SAW resonator 5 and the pad 43, or connects the SAW resonators 5 to each other. A wiring 41 that intersects with a wiring 41 made of the same conductor layer as the conductor layer constituting the IDT electrode 23 via an insulating layer may be provided.

The penetrating conductor 45 is formed in a columnar shape standing on the pad 43, for example, and penetrates the frame portion 17 and the lid portion 19. The through conductor 45 is made of, for example, a metal such as Cu. The through conductor 45 may be made of a plurality of materials. For example, the inner surface and the outer peripheral surface may be made of different materials. A part of the plurality of terminals 9 (for example, 9A and 9K) is arranged on the through conductor 45. The through conductor 45 may be integrally made of the same material as the plurality of terminals 9 and the reinforcing layer 11.

Further, as shown in FIG. 4A, the other part (for example, 9L) of the plurality of terminals 9 is not provided on the through conductor 45 and is connected to the through conductor 45 via the reinforcing layer 11. Has been done.

It should be noted that the terminal 9 not on the through conductor 45 and the reinforcing layer 11 may be appropriately distinguished from each other. For example, when the SAW device 1 is surface-mounted on a circuit board (not shown) by bumps (not shown), it can be specified by the joining position of the bumps. Further, for example, the position of the terminal 9 may be specified based on the pamphlet and the specifications of the SAW device 1, and the terminal 9 and the reinforcing layer 11 may be distinguished from each other.

Further, as shown in FIGS. 4A and 4B, when the insulating layer 47 made of a solder resist or the like is provided on the reinforcing layer 11, the portion exposed from the insulating layer 47 is provided. May be specified as the terminal 9. The insulating layer 47 contributes to reducing, for example, the possibility that an unintended short circuit will occur due to bumps. The insulating layer 47 may not be provided.

Further, as shown in FIG. 4B, the first metal layer 49 constituting the terminal 9 and the reinforcing layer 11 and the surface of the terminal 9 are formed on the cover 7 (the surface of the reinforcing layer 11 is not formed). When the second metal layer 51 is provided, the region where the second metal layer 51 is arranged may be specified as the terminal 9. The first metal layer 49 is composed of, for example, Cu, and the second metal layer 51 is composed of, for example, Au or Ag. The second metal layer 51 contributes to, for example, improving the joint strength between the terminal 9 and the bump and / or preventing corrosion of the terminal 9. The second metal layer 51 may not be provided.

(Plane shape of reinforcement layer)
FIG. 5 is a plan view of the SAW device 1.

In this figure, the penetrating conductor 45 is also shown by a dotted line. In the illustrated example, of the terminals 9A to 9L, the terminals 9A, 9C, 9E, 9G and 9K are located on the through conductor 45, and the other terminals 9 are separated from the through conductor 45.

The reinforcing layer 11 includes a plurality of elongated patterns extending in a predetermined direction in a plan view. The plurality of elongated patterns have, for example, bus conductors 55A and 55B and strip conductors 57A and 57B which are narrower than the bus conductors 55A. The reinforcing layer 11 includes a conductor pattern that is difficult to classify into a long pattern (concept that it extends in a predetermined direction), such as the area pattern 56 connected to the terminal 9H. May be good.

The bus conductor 55A and the strip conductor 57A with the additional reference numerals A are, for example, conductors extending in a direction orthogonal to the propagation direction of SAW (D1 axis direction) (direction parallel to the electrode finger 31). The bus conductor 55B and the strip conductor 57B with the additional reference numeral B are, for example, conductors extending in the propagation direction of SAW (the D1 axial direction, the direction orthogonal to the electrode finger 31). In other embodiments described later, the correspondence between the additional symbols A and B of the bus conductor 55 and the strip conductor 57 and the propagation direction of the SAW is the same as described above.

Since the reinforcing layer 11 is composed of the bus conductor 55 and the strip conductor 57, a plurality of non-arranged regions of the reinforcing layer 11 and the terminals 9 are formed on the upper surface 7a of the cover 7. The total area of the reinforcing layer 11 and the terminal 9 may be appropriately set. For example, the total area of the reinforcing layer 11 and the terminal 9 is 2/3 or less or 1/2 or less of the area of the upper surface 7a.

As will be described in detail later, the bus conductor 55 is directly or indirectly connected to the through conductor 45 via the terminal 9 or the like, and is connected to the IDT electrode 23 via the pad 43 and the wiring 41. Similarly, the strip conductor 57 is directly or indirectly connected to the through conductor 45 via the bus conductor 55 or the like, and is connected to the IDT electrode 23 via the pad 43 and the wiring 41. In other words, the bus conductor 55 or the strip conductor 57 is connected to the IDT electrode 23 by a connecting conductor (through conductor 45, pad 43, wiring 41, etc.) at least partially located in the cover 7. As a result, a heat dissipation path from the IDT electrode 23 to the bus conductor 55 or the strip conductor 57 is configured.

(Bus conductor)
The bus conductor 55 extends linearly with a constant width, for example. The width of the bus conductor 55 may be appropriately set. For example, the width of the bus conductor 55 is substantially the same as the width of the terminal 9 (the size of the terminal 9 in the width direction of the bus conductor 55 connected to the terminal 9; the diameter when the terminal 9 is circular). .. The substantially equivalent here is, for example, a state in which the difference between the two is ± 20% or less of the width of the terminal 9. Of course, the width of the bus conductor 55 may be smaller or larger than the width of the terminal 9.

The total number or areas of the plurality of bus conductors 55 may be appropriately set. For example, the total area of the bus conductors 55 (both 55A and 55B) is less than 1/2 or less than 1/3 of the area of the top surface of the cover 7. Further, the number of bus conductors 55A and 55B may be large. Similarly, the total area of the bus conductor 55A and the total area of the bus conductor 55B may be larger. In the illustrated example, the number of bus conductors 55A and 55B (or the total area) is almost the same, and the number of bus conductors 55A is slightly larger than that of the bus conductor 55B (or the total area is larger).

The plurality of bus conductors 55 may be arranged at appropriate positions on the upper surface 7a of the cover 7 with appropriate lengths. For example, in FIG. 5, a bus conductor 55 is provided adjacent to the outer edge (one side) of the upper surface 7a and extends along the outer edge with a length shorter than the outer edge. Further, a bus conductor 55 extending inward of the upper surface 7a from a position adjacent to the outer edge of the upper surface 7a is provided. In addition, although not particularly shown, a bus conductor 55 that is adjacent to the outer edge (one side) of the upper surface 7a and extends along the outer edge with a length substantially equal to that of the outer edge, and a bus that extends at a position away from the outer edge of the upper surface 7a. A conductor 55 or a bus conductor 55 that traverses or traverses the upper surface 7a (that is, extends from the outer edge to the outer edge) may be provided. In the above, the fact that the bus conductor 55 is adjacent to the outer edge of the upper surface 7a means that, for example, the distance between the bus conductor 55 and the outer edge is smaller than the width of the bus conductor 55.

The positions of the plurality of bus conductors 55 with respect to the space 21 (from another viewpoint, the frame portion 17) are also arbitrary. For example, among the plurality of bus conductors 55, the bus conductor 55 extending along the outer edge of the upper surface 7a described above has at least the outer edge side overlapping the frame portion 17, and is supported by the frame portion 17 via the lid portion 19. There is. Further, for example, the bus conductor 55 extending inward from the outer edge of the upper surface 7a is supported by the frame portion 17 via the lid portion 19 on the outer edge side and overlaps the space 21 on the inner side. When a plurality of spaces 21 are configured, the bus conductor 55 may be located on a wall portion (frame portion 17) that partitions the plurality of spaces 21. Further, unlike the illustrated example, the bus conductor 55 that overlaps the space 21 may not be present in the plan perspective.

The plurality of bus conductors 55 may be arranged in an appropriate positional relationship with each other, and may be appropriately connected to form a predetermined shape with or without the terminal 9. For example, two bus conductors 55 may be connected so as to form an L shape (see the vicinity of terminal 9F), or three bus conductors 55 may be connected so as to form three sides of a rectangle. Alternatively, four bus conductors 55 may be connected so as to form four sides of the rectangle (see near terminals 9D and 9E), or may be connected (see near terminals 9A, 9B and 9L). In addition, two bus conductors 55 (which may be regarded as three) are connected so as to form a T-shape, and two (may be regarded as four) so as to form a cross. The bus conductor 55 of the above may be connected.

The bus conductor 55 extends from, for example, the terminal 9. The terminal 9 connected to the bus conductor 55 may be one located on the through conductor 45 (9A or the like) or may be separated from the through conductor 45 (9L or the like). The terminal 9 connected to the bus conductor 55 is, for example, a terminal to which a reference potential is applied. Note that, unlike the illustrated example, the bus conductor 55 may be separated from the terminal 9, and instead of the terminal 9 to which the reference potential is applied, the bus conductor 55 extends from the terminal 9 to which the signal is input or output. May be good.

In the following description, for example, the terminal 9I is not located in the middle of one bus conductor 55B, but two bus conductors 55B extend from the terminal 9I on opposite sides to each other. The number of bus conductors 55 is counted based on the way of thinking. At this time, the number of bus conductors 55 extending from one terminal 9 may be any of 1 to 4. The bus conductor 55 may or may not contribute to the electrical connection of the two terminals 9.

The shape (L-shape or the like) formed by the plurality of bus conductors 55 and the connection mode between the bus conductors 55 and the terminals 9 may be appropriately combined.

For example, in FIG. 5, the terminal 9L away from the through conductor 45 is located at the apex of the L shape formed by the two bus conductors 55. In other words, (at least) two bus conductors 55 (55A and 55B) extend from the terminal 9L in a direction intersecting (for example, orthogonally) with each other. The same applies to terminals 9B, 9D, 9F, 9I and 9J (these are terminals 9 separated from the through conductor 45).

Further, for example, the terminal 9L away from the through conductor 45 is located at one apex of one of the three sides of the rectangle formed by the three bus conductors 55. In other words, the bus conductors 55A and 55B extending from the terminal 9L are provided, and the bus conductor 55A extending from the terminal 9 extends in parallel with the bus conductor 55B extending from the terminal 9L from a position away from the terminal 9L. A bus conductor 55B is provided (A and B may be reversed). The same applies to terminals 9B, 9D, 9I and 9J (these are terminals 9 separated from the through conductor 45).

Further, for example, the terminal 9L away from the through conductor 45 is located at one apex of the four sides of the rectangle formed by the four bus conductors 55. In other words, the bus conductors 55A and 55B extending from the terminal 9L are provided, and the bus conductors 55B and 55A extending from the terminal 9L from a position away from the terminal 9L of the bus conductors 55A and 55B extending from the terminal 9. Bus conductors 55B and 55A extending in parallel are provided in parallel. The same applies to the terminal 9B (the terminal 9 is separated from the through conductor 45).

Although attention is paid to the terminal 9 that is separated from the through conductor 45, the same shape formed by the bus conductor 55 and the positional relationship between the terminal 9 may be established for the terminal 9 on the through conductor 45.

(Strip conductor)
The strip conductor 57 extends linearly with a constant width, for example. The width of the strip conductor 57 may be appropriately set. For example, the width of the strip conductor 57 is 1/2 or less or 1/4 or less of the width of the bus conductor 55 (in another viewpoint, the width or the maximum diameter of the terminal 9).

The total number or area of the plurality of strip conductors 57 may be appropriately set. For example, the number of plurality of strip conductors 57 (total of 57A and 57B) is larger than the number of plurality of bus conductors 55 (total of 55A and 55B). Further, for example, the total area of the plurality of strip conductors 57 may be larger, equal to, or smaller than the total area of the plurality of bus conductors 55.

The number of strip conductors 57A and 57B may be large. Similarly, the total area of the strip conductor 57A and the total area of the strip conductor 57B may be larger. In the present embodiment, the number of strip conductors 57A extending in the direction orthogonal to the propagation direction of SAW (D2 axis direction) is larger (or the total area is larger) than the number of strip conductors 57B extending in the propagation direction of SAW. For example, the number (or total area) of the strip conductors 57A is more than twice the number (or total area) of the strip conductors 57B, and is 5 times or more or 10 times or more.

The plurality of strip conductors 57 may be arranged at appropriate positions on the upper surface 7a of the cover 7 with appropriate lengths. For example, the strip conductor 57 may or may not have a length that generally traverses or traverses the top surface 7a. The positions of the plurality of bus conductors 55 with respect to the space 21 (from another viewpoint, the frame portion 17) may be appropriately set. However, for example, at least a part or the whole of the strip conductor 57 in the length direction overlaps the space 21.

The plurality of strip conductors 57 may be arranged in an appropriate positional relationship with each other, or may be appropriately connected to form a predetermined shape. In the illustrated example, a relatively large number of strip conductors 57A are arranged at substantially even pitches in the SAW propagation direction. The strip conductor 57B intersects the plurality of strip conductors 57A. In the description of the present embodiment, when the strip conductor 57A and the strip conductor 57B intersect, it is assumed that the intersection includes not only the intersection forming a cross but also the intersection forming a T-shape or an L-shape.

When focusing on the strip conductors 57A and 57B that intersect each other as described above instead of the entire strip conductor 57 on the upper surface 7a of the cover 7, the number of strip conductors 57A and 57B is large. It may be (the total area may be large). In the illustrated example, the strip conductor 57A has a larger number (or a larger total area) than the strip conductor 57B. For example, the number (or total area) of the strip conductors 57A is more than twice or more than five times the number (or total area) of the strip conductors 57B.

The plurality of strip conductors 57 extend from, for example, the bus conductor 55 (connected to the bus conductor 55). In the description of the present embodiment, the strip conductor 57 extends from the bus conductor 55 even if the strip conductor 57 and the bus conductor 55 can be regarded as intersecting with each other so as to form a cross. (Strip conductors 57 on opposite sides of the bus conductor 55 are expressed as different from each other.)

As illustrated in FIG. 5, the strip conductor 57 and the bus conductor 55 connected to each other may extend in a direction intersecting each other (that is, the strip conductor 57B extends from the bus conductor 55A. Alternatively, the strip conductor 57A may extend from the bus conductor 55B), may extend in the same direction as each other (that is, the strip conductor 57A extends from the bus conductor 55A, or the strip conductor 57B extends from the bus conductor 55B. It may be extended).

Further, for example, the plurality of strip conductors 57 are connected (intersected) with the strip conductors 57 extending from the bus conductor 55. For example, in the example of FIG. 5, one strip conductor 57B extends from the bus conductor 55A extending in the −D2 direction from the terminal 9J in the + D1 axial direction, and a plurality of strip conductors 57A are provided with respect to the strip conductor 57B. It intersects.

Further, for example, the plurality of strip conductors 57 extend from the area pattern 56 connected to the terminal 9H. Alternatively, the plurality of strip conductors 57 intersect the strip conductors 57 extending from the area pattern 56.

Some of the plurality of strip conductors 57 may contribute to the electrical connection between the terminals 9. For example, a plurality of strip conductors 57 located between the terminals 9F and 9H contribute to these connections. In this example, the plurality of strip conductors 57 directly connect the bus conductor 55 connected to the terminal 9F and the area pattern 56 connected to the terminal 9H. In addition, the strip conductor 57 may electrically connect the terminals 9 to each other, for example, by connecting the bus conductors 55 to each other or connecting the area patterns 56 to each other.

Although not particularly shown, the strip conductor 57 may exist alone without being connected to the bus conductor 55, the area pattern 56, the terminal 9, and the other strip conductor 57. Further, for example, a plurality of strip conductors 57 connected to each other (crossing each other) may exist without being connected to the bus conductor 55, the area pattern 56, and the terminal 9.

The positional relationship of the plurality of strip conductors 57 with respect to the positional relationship between the plurality of bus conductors 55 (the shape formed by the plurality of bus conductors 55) may be appropriately set. For example, the bus conductor 55B extending from the terminal 9A in the −D1 direction and the bus conductor 55B extending from the terminal 9L in the −D1 direction extend in parallel with each other so as to be bridged over the two bus conductors 55B. Is provided with a plurality of strip conductors 57A. Further, from another viewpoint, the plurality of strip conductors 57A are bridged over the two bus conductors 55 inside the three or four sides of the rectangle composed of the plurality of bus conductors 55.

(Relative position of strip conductor with respect to IDT electrode)
FIG. 6A is a perspective perspective view showing an example of the position of the strip conductor 57 relative to the IDT electrode 23 (SAW resonator 5).

As described above, the strip conductor 57A extends in a direction parallel to the electrode finger 31 of the IDT electrode 23, and thus the plurality of strip conductors 57A are arranged in the arrangement direction of the plurality of electrode fingers 31. There is. Further, the strip conductor 57B extends in a direction orthogonal to the electrode finger 31.

The plurality of strip conductors 57A are arranged, for example, at a pitch larger than the pitch of the plurality of electrode fingers 31 but smaller than the size of the IDT electrode 23 in the SAW propagation direction (D1 axis direction). As a result, the plurality of strip conductors 57A overlap the arrangement regions of the plurality of electrode fingers 31. On the other hand, the strip conductor 57B does not overlap the arrangement regions of the plurality of electrode fingers 31, for example. The arrangement region of the plurality of electrode fingers 31 is, for example, a region surrounded by the electrode fingers 31 at both ends in the arrangement direction of the plurality of electrode fingers 31 and the edges of the pair of bus bars 29 facing each other (that is,). , The region excluding the arrangement region of the pair of bus bars 29 from the arrangement region of the IDT electrode 23).

More specifically, for example, two IDT electrodes 23 are connected in series, and the strip conductor 57B is located between them. In the illustrated example, the two IDT electrodes 23 are connected by the wiring 41, and the strip conductor 57B is located on the wiring 41. However, the two IDT electrodes 23 may be directly connected to each other in the bus bars 29, or the strip conductor 57B may at least partially overlap the bus bars 29 located between the two IDT electrodes 23. ..

The two (two or more) IDT electrodes 23 (SAW resonators 5) connected in series constitute, for example, one series resonator or one parallel resonator in a ladder type SAW resonator filter. .. That is, as a design idea, the two SAW resonators 5 are obtained by dividing one SAW resonator into two or more. Such division is advantageous for improving the power resistance, for example.

It should be noted that the strip conductor 57B is arranged so as not to overlap the arrangement area of the plurality of electrode fingers 31 and / or the strip conductor 57A does not overlap the arrangement area of the plurality of electrode fingers 31 without having such a relative relationship. It may be done.

(Modification example of strip conductor)
FIG. 6B is a plan view showing a modified example of the strip conductor 57. As shown in this figure, the strip conductor 57 may extend from the terminal 9. In the illustrated example, the end of the strip conductor 57 on the opposite side of the terminal 9 is not connected to another conductor. Of course, the opposite end is connected to another terminal 9, a bus conductor 55, an area pattern 56 or a strip conductor 57 (here 57B) extending in a direction orthogonal to the illustrated strip conductor 57 (here 57A). You may be. Further, another strip conductor 57 (here 57B) (not shown here) may intersect with the intermediate position of the illustrated strip conductor 57 (here 57A).

(Relationship between width and thickness of strip conductor)
FIG. 6C is a cross-sectional view taken along the line VIc-VIc of FIG.

The thickness t1 of the strip conductor 57 (reinforcing layer 11) is larger than, for example, the width w1 of the strip conductor 57. For example, the thickness t1 is 1 μm or more, or 4 μm or more larger than the width w1. From another point of view, for example, the thickness t1 is 5% or more, or 20% or more larger than the width w1. As an example, for example, the width w1 is about 20 μm and the thickness t1 is about 25 μm. However, the thickness t1 may be the same as the width w1 or may be smaller than the width w1.

As described above, in the present embodiment, the SAW apparatus 1 is mounted on the piezoelectric substrate 13, the support substrate 15 which is bonded to the lower surface of the piezoelectric substrate 13 and has a smaller thermal expansion coefficient than the piezoelectric substrate 13, and the piezoelectric substrate 13. A plurality of IDT electrodes 23 that are located, a cover 7 that forms a space 21 on the IDT electrode 23, and a plurality of covers 7 that extend in parallel on the cover 7 and at least partially overlap the space 21 in plan perspective. The strip conductor 57 and the like.

Therefore, for example, the support substrate 15 suppresses the thermal expansion of the piezoelectric substrate 13, and thus the change in electrical characteristics due to the temperature change is suppressed. That is, a temperature compensation effect can be obtained. Further, for example, the rigidity of the cover 7 can be strengthened by the plurality of strip conductors 57, and the possibility that the cover 7 bends toward the space 21 can be reduced.

Here, the reinforcing layer (conductor) generally has a larger coefficient of thermal expansion than the piezoelectric substrate 13 and a relatively large Young's modulus (for example, larger than the cover 7). Therefore, for example, when a solid reinforcing layer is provided on the upper surface 7a of the cover 7, tensile stress may be applied to the piezoelectric substrate 13 due to thermal expansion of the reinforcing layer. As a result, the temperature compensation effect of the support substrate 15 may be reduced.

However, in the SAW device 1, since the reinforcing layer 11 is composed of a plurality of strip conductors 57, the possibility that the effect of the support substrate 15 is reduced is reduced as compared with the embodiment in which the solid reinforcing layer is provided. To. Further, for example, the reinforcing layer 11 has a larger surface area with respect to the volume as compared with the solid reinforcing layer, so that the efficiency of heat dissipation with respect to the volume is improved.

In this embodiment, the SAW apparatus 1 further has a bus conductor 55 extending on the cover 7 with a width wider than each of the plurality of strip conductors 57. The plurality of strip conductors 57 extend from the bus conductor 55.

Therefore, for example, the plurality of strip conductors 57 will be supported by the bus conductor 55, and the effect of reinforcing the cover 7 by the plurality of strip conductors 57 will increase. Further, for example, by connecting the plurality of strip conductors 57 to the bus conductor 55 having a relatively large cross-sectional area and easily transmitting heat, it becomes easy to transfer heat between the plurality of strip conductors 57, and the heat is biased. This eliminates the problem and makes it easier to dissipate heat evenly (efficiently) from the plurality of strip conductors 57.

In this embodiment, the SAW device 1 extends in parallel with one bus conductor 55 and the bus conductor 55, as illustrated near terminals 9A and 9L, and is more than a plurality of strip conductors 57. It further has another bus conductor 55 with a wide width. The plurality of strip conductors 57 are bridged between the two bus conductors 55 described above.

Therefore, for example, the plurality of strip conductors 57 are supported at both ends by the bus conductors 55, and the effect of reinforcing the cover 7 by the plurality of strip conductors 57 is further increased. Further, the effect of transferring heat between the plurality of strip conductors 57 is improved, and the heat dissipation property is also improved.

In the present embodiment, the SAW apparatus 1 has a plurality of strip conductors 57 (57A in the present embodiment) extending in parallel with each other, and one or more strip conductors 57B intersecting the plurality of strip conductors 57A. There is. In the plurality of strip conductors 57A and one or more strip conductors 57B intersecting with each other, the number of one or more strip conductors 57B is less than 1/2 of the number of the plurality of strip conductors 57A.

Therefore, for example, when the plurality of strip conductors 57A are connected to each other by one or more strip conductors 57B, heat is easily transferred between the plurality of strip conductors 57A, the heat bias is eliminated, and the heat dissipation effect is improved. be able to. Although not shown in particular, this has been confirmed by simulation calculations performed by the inventor of the present application. On the other hand, since the number of strip conductors 57B is relatively small, for example, the tensile stress in the extending direction of the strip conductors 57B generated in the piezoelectric substrate 13 due to the thermal expansion of the strip conductors 57B is reduced. Will be done.

It should be noted that a mode in which a meander type inductor is formed by strip conductors 57A and 57B (this mode may also be included in the technique according to the present disclosure) will be considered. In this inductor, when the inductor is divided so that the number of strip conductors 57B is minimized with respect to the number of strip conductors 57A, a combination of one strip conductor 57B and two strip conductors 57A is extracted. That is, even if the inductor is divided so that the number of strip conductors 57B is minimized with respect to the number of strip conductors 57A, the number of strip conductors 57B is 1/2 of that of strip conductors 57A. Therefore, the fact that the number of strip conductors 57B is less than 1/2 of the number of strip conductors 57A also indicates a difference from the meander type inductor.

In this embodiment, the excitation electrode is an IDT electrode 23 having a plurality of electrode fingers 31 extending in parallel with each other. The plurality of strip conductors 57A, which are relatively large in number among the strip conductors 57A and 57B, extend in the direction in which the plurality of electrode fingers 31 extend.

That is, the number of strip conductors 57B that intersect (for example, orthogonally) the plurality of electrode fingers 31 is reduced. As a result, for example, the tensile stress applied to the piezoelectric substrate 13 from the reinforcing layer 11 (strip conductor 57B) in the propagation direction of SAW is reduced. On the other hand, as for the expansion of the piezoelectric substrate 13, the expansion in the propagation direction of the SAW affects the electrical characteristics of the SAW device 1. Therefore, for example, the decrease in the temperature compensation effect due to the support substrate 15 is effectively reduced.

In the present embodiment, as described above, one or more strip conductors 57B intersecting the plurality of strip conductors 57A and having a relatively small number do not overlap with the plurality of electrode fingers 31 in plan perspective, for example.

Therefore, for example, the possibility that an unintended electrical coupling will occur between the strip conductor 57B and the IDT electrode 23 is reduced. That is, the possibility that the strip conductor 57B affects the characteristics of the SAW device 1 is reduced. Since the number of strip conductors 57B is small, such an arrangement is possible.

In the present embodiment, the plurality of strip conductors 57 have a thickness larger than a width.

Therefore, for example, in the strip conductor 57, the moment of inertia of area related to the bending deformation toward the space 21 side is relatively large with respect to the cross-sectional area. As a result, for example, it is possible to reduce the thermal stress exerted on the piezoelectric substrate 13 in the plane direction while maintaining the effect of reducing the possibility that the cover 7 bends toward the space 21 side.

In the present embodiment, the SAW device 1 is at least partially located in the cover 7, and is a connecting conductor (for example, a wiring 41, a pad 43, a penetrating conductor) connecting the IDT electrode 23 and the plurality of strip conductors 57. It further has 45, a terminal 9 and a bus conductor 55).

Therefore, for example, a heat transfer path from the IDT electrode 23 to the strip conductor 57 is configured. As a result, in the IDT electrode 23, the characteristic change due to the temperature change is reduced. Further, for example, when the strip conductor 57 is connected to the terminal 9 to which the reference potential is applied, the volume of the conductor to which the reference potential is applied increases, so that the reference potential becomes stable. As a result, for example, the characteristics of the SAW device 1 are improved.

Further, in the present embodiment, in the SAW device 1, a plurality of strip conductors 57A are connected to one bus conductor 55B. The plurality of strip conductors 57A are arranged at substantially the same pitch.

Therefore, the strip conductor 57A functions like a beam, and it is possible to prevent the lid portion 19 from being deformed toward the space 21. Further, since the strip conductors 57A are arranged at a uniform pitch, stress from the outside can be dispersed, so that the reliability of the SAW device 1 can be improved.

Further, from the above configuration, even if the distance between the plurality of strip conductors 57A is larger than the width of the strip conductors 57A, the deformation of the lid portion 19 can be suppressed. Further, by increasing the distance between the plurality of strip conductors 57A with respect to the width of the strip conductor 57A, it is possible to reduce the thermal stress exerted on the piezoelectric substrate 13 in the plane direction.

In the present embodiment, from another viewpoint, the SAW apparatus 1 includes the piezoelectric substrate 13, the IDT electrode 23 located on the piezoelectric substrate 13, the cover 7 covering the IDT electrode 23, and at least the upper surface of the cover 7. A through conductor 45 electrically connected to the IDT electrode 23 penetrating the 7a side portion, and a terminal 9 (for example, terminal 9L) located on the cover 7 and separated from the through conductor 45 in a plan view. , 9B, 9D, 9F, 9I or 9J) and a reinforcing layer 11 located on the cover 7 and connecting the through conductor 45 and the terminal 9 away from the through conductor 45. are doing. The reinforcing layer 11 has bus conductors 55A and 55B extending in directions intersecting with each other starting from a terminal 9 away from the through conductor 45.

Therefore, for example, when a force is applied to the mounted SAW device 1 in the plane direction (D1 axial direction and / or D2 axial direction), the risk of deformation or breakage of the SAW device 1 is reduced. That is, the shear stress resistance can be improved. Specifically, for example, it is as follows.

The SAW device 1 is mounted on a circuit board, for example, by joining a plurality of terminals 9 and a circuit board (not shown) by bumps (not shown). Therefore, when a force in the plane direction is applied to the mounted SAW device 1, this force is applied to the plurality of terminals 9. Here, for example, since the terminal 9 on the through conductor 45 receives a reaction force from the through conductor 45 having a Young's modulus larger than that of the cover 7, displacement in the plane direction with respect to the piezoelectric substrate 13 or the cover 7 is unlikely to occur. On the other hand, at the terminal 9 away from the through conductor 45, since such a reaction force cannot be obtained, displacement with respect to the piezoelectric substrate 13 or the cover 7 is likely to occur. As a result, deformation or breakage is likely to occur in the terminal 9 and its surroundings away from the through conductor 45. For example, the terminal 9 deviates from the original position on the cover 7. As a result, for example, a short circuit or disconnection may occur.

However, in the present embodiment, the bus conductors 55A and 55B extend from the terminal 9 away from the through conductor 45 in the direction of intersecting each other. Since the bus conductor 55A is in close contact with the cover 7 for a relatively long distance in the extending direction (D2 axis direction), it is difficult to be displaced in the extending direction. Since the bus conductor 55A extends from the terminal 9 as a starting point, the terminal 9 is suppressed from being displaced in the extending direction of the bus conductor 55A. Similarly, the terminal 9 separated from the through conductor 45 is suppressed from being displaced in the extending direction (D1 axis direction) of the bus conductor 55B. As a result, the terminal 9 separated from the through conductor 45 is suppressed from being displaced in the plane direction. As a result, deformation or breakage of the terminal 9 and its surroundings is suppressed.

In the present embodiment, the reinforcing layer 11 further has, for example, a bus conductor 55B extending in parallel with the bus conductor 55B extending from the terminal 9L and connected to the bus conductor 55A extending from the terminal 9L (this). The connection may or may not be via the terminal 9, and in the present embodiment, the connection is via the terminal 9A). That is, the bus conductors 55A and 55B are provided so that the three sides of the rectangle are formed.

Therefore, for example, the displacement of the terminal 9L in the plane direction is accompanied by deformation of the three sides of the rectangle (for example, deformation that changes the angle formed by the two sides). As a result, for example, the terminal 9L is more likely to obtain a reaction force from the reinforcing layer 11. As a result, the shear stress resistance is further improved. In particular, when the bus conductor 55A and the bus conductor 55B are provided so as to form the four sides of the rectangle, this effect is enhanced.

In the present embodiment, the reinforcing layer 11 has, for example, a plurality of strip conductors 57A extending from the bus conductors 55A and 55B extending from the terminal 9L and narrower than the bus conductors 55A and 55B. ..

Therefore, for example, the displacement of the terminal 9L is further suppressed in the extending direction of the strip conductor 57A. Further, the area of the reinforcing layer 11 can be reduced as compared with the case where the plurality of bus conductors 55A extend from the bus conductors 55B. As a result, for example, the tensile stress generated in the piezoelectric substrate 13 due to the thermal expansion of the reinforcing layer 11 can be reduced, and the possibility that the characteristics of the SAW device 1 will change can be reduced. This effect becomes remarkable when a plurality of strip conductors 57 are arranged in the propagation direction of SAW.

In the present embodiment, the reinforcing layer 11 is bridged between, for example, a bus conductor 55B extending from the terminal 9L and a bus conductor 55B (extending from the terminal 9A) extending in parallel with the bus conductor 55B, and the bus. It has a plurality of strip conductors 57A that are narrower than the conductors 55A and 55B.

Therefore, for example, the displacement of the terminal 9L in the plane direction involves a deformation of the shape composed of the pair of bus conductors 55B and the plurality of strip conductors 57A. As a result, for example, the terminal 9L is more likely to obtain a reaction force from the reinforcing layer 11. Further, the area of the reinforcing layer 11 can be reduced as compared with the case where a plurality of bus conductors 55A are bridged between the pair of bus conductors 55B.

In the present embodiment, the SAW device 1 further includes a support substrate 15 which is attached to the lower surface of the piezoelectric substrate 13 and has a coefficient of thermal expansion smaller than that of the piezoelectric substrate 13. The reinforcing layer 11 is configured to include the bus conductor 55.

Therefore, for example, similar to the effect of forming the reinforcing layer 11 with a plurality of strip conductors, the reinforcing layer 11 has a temperature compensation effect of the support substrate 15 as compared with the case where the solid reinforcing layer is provided. The risk of being reduced is reduced.

In the first embodiment, the SAW device 1 is an example of an elastic wave device. The IDT electrode 23 is an example of an excitation electrode. The strip conductor 57A is an example of the first strip conductor. The strip conductor 57B is an example of the second strip conductor. The bus conductor 55B is an example of the first bus conductor and the second bus conductor. The reinforcing layer 11 is an example of a conductor layer. The bus conductors 55A or 55B are examples of the first extension portion to the fourth extension portion.

Further, in the above example, the pad 43 is electrically led out to the upper surface of the cover 7 by the penetrating conductor 45 penetrating the cover 7, but this is not the case. For example, a lead-out electrode in which the cover 7 is arranged so that the pad 43 is located outside the outer peripheral edge of the cover 7, and a part of the outer surface of the cover 7 is continuously covered from the upper surface of the pad 43 to the upper surface of the cover 7. May be provided. In this case, the cover 7 can be reinforced with the lead-out electrode and the intrusion of moisture and the like can be prevented.

Further, in the above description, a configuration in which solder or the like is formed on the terminal 9 and the SAW device 1 is mounted on the circuit board has been described, but the present invention is not limited to this. FIG. 13 shows a modified example of the SAW device 1. FIG. 13 is a cross-sectional view at a position corresponding to the line XIII-XIII in FIG.

As shown in FIG. 13, a relatively thick insulating layer 47 may be provided on the lid 19. In this case, for example, the insulating layer 47 may have a height (thickness) equal to or higher than that of the space 21. The insulating layer 47 is formed of, for example, a solder resist as in FIG.

An upper penetrating conductor 44 located on the terminal 9 and penetrating through the insulating layer 47 in the thickness direction is provided, and solder is formed on the upper penetrating conductor 44 to facilitate mounting on the circuit board. May be good.

In this case, stress is transmitted from the solder to the terminal 9 via the upper through conductor 44. When the penetrating conductor 45 is provided directly below the terminal 9, since there are a series of penetrating conductors (45, 44) above and below the terminal 9, it is possible to counter stress in the surface direction applied to the terminal 9.

On the other hand, when the terminal 9 is separated from the through conductor 45, that is, when there is no through conductor 45 directly under the terminal 9 and the upper through conductor 44 is located only directly above the terminal 9, the stress in the surface direction applied to the terminal 9 is applied. The power to oppose is weakened. However, since the bus conductors 55A and 55B extend from the terminal 9 as a starting point, it is possible to increase the force of the bus conductor 55 against the stress applied to the terminal 9 in the surface direction.

When the SAW device 1 having the configuration shown in FIG. 13 was mounted on a circuit board and a die share test was performed, neither the terminal 9 was peeled off nor the insulating layer 47 and the cover 7 were peeled off. On the other hand, the SAW device of the comparative example was different from the SAW device 1 only in that it was not provided with the bus conductor 55 extending from the terminal 9, and the other points were the same as those of the SAW device 1 shown in FIG. As a result of the same test, in the SAW apparatus of the comparative example, the terminal 9 at a position away from the through conductor 45 was peeled off from the cover 7, and the insulating layer 47 and the cover 7 were also peeled off. From the above, it was confirmed that the bus conductor 55 can enhance the reliability of the SAW device 1.

<Second Embodiment>
FIG. 7 is a plan view showing the configuration of the SAW device 201 according to the second embodiment. This figure corresponds to FIG. 5 of the first embodiment.

The SAW device 201 is different from the SAW device 1 in the specific shape of the reinforcing layer, and is the same in other respects. The number of bus conductors 55 in the reinforcing layer 211 of the SAW device 201 is reduced as compared with the reinforcing layer 11 of the SAW device 1. Along with this, the arrangement area of the plurality of strip conductors 57 is wider than that of the first embodiment.

<Third Embodiment>
FIG. 8 is a plan view showing the configuration of the SAW device 301 according to the third embodiment. This figure corresponds to FIG. 5 of the first embodiment.

The SAW device 301 is different from the SAW device 1 in the specific shape of the reinforcing layer, and is the same in other respects. In the reinforcing layer 11 of the SAW device 1, the number of strip conductors 57A was larger than the number of strip conductors 57B. On the other hand, in the reinforcing layer 311 of the SAW device 301, the number of strip conductors 57B is larger than the number of strip conductors 57A. In the SAW device 301, the arrangement of the bus conductor 55 is the same as that in the SAW device 1.

<Fourth Embodiment>
FIG. 14 is a plan view showing the configuration of the SAW device 401 according to the fourth embodiment. This figure corresponds to FIG. 5 of the first embodiment.

The SAW device 401 is different from the SAW device 1 in the specific shape of the reinforcing layer, and is the same in other respects. The reinforcing layer 411 of the SAW device 401 has a shape in which the plurality of strip conductors 57 are omitted in the reinforcing layer 11 of the SAW device 1.

Even in such a configuration, for example, the shear stress resistance is improved by providing the bus conductors 55A and 55B extending in the directions intersecting with each other starting from the terminal 9 away from the through conductor 45.

(Modification example of through conductor)
FIG. 15 is a cross-sectional view showing a modified example of the through conductor. This figure corresponds to FIG. 4 (a).

As shown on the left side of the paper, the penetrating conductor 45 penetrating the entire cover 7 is not provided, but the penetrating conductor 46A penetrating the frame portion 17 (the lower surface side portion of the cover 7 from another viewpoint) and the lid portion 19 A through conductor 46B penetrating (a portion on the upper surface side of the cover 7 from another viewpoint) and an internal wiring 42 connecting the through conductors 46A and 46B may be provided.

The through conductor 46A is located, for example, on the pad 43. The through conductor 46B is separated from the through conductor 46A in a plan view. The internal wiring 42 is composed of a layered conductor extending parallel to the upper surface 13a of the piezoelectric substrate 13 between the frame portion 17 and the lid portion 19 (in another viewpoint, inside the cover 7). The terminal 9 may be connected to the through conductor 46B via a reinforcing layer 11 (for example, a bus conductor 55) as in the illustrated example, or is provided on the through conductor 46B and is provided on the through conductor 46B unlike the drawing. It may be connected to 46B.

By using such through conductors 46A and 46B and the internal wiring 42, restrictions on the connection position between the through conductor (46B) and the reinforcing layer 11 (bus conductor 55) due to the position of the pad 43 on the piezoelectric substrate 13 are relaxed. Will be done. As a result, for example, the through conductor 46B can be arranged at an appropriate position so that the displacement of the bus conductor 55 can be suppressed by the through conductor 46B. As a result, it becomes easy to improve the shear stress resistance.

<Demultiplexer>
FIG. 9 is a circuit diagram schematically showing the configuration of the SAW device 1 when the SAW device 1 (or 201, 301 or 401) is a duplexer. As can be understood from the reference numerals shown in the upper left of the paper in this figure, the comb tooth electrode 27 is schematically shown by a bifurcated fork shape in this figure.

The demultiplexer 101 is, for example, a pair of a transmission filter 109 that filters a transmission signal from a transmission terminal (for example, 9K) and outputs it to an antenna terminal (for example, 9C) and a pair of a transmission filter 109 that filters a reception signal from the antenna terminal 9C. It has a reception filter 111 that outputs to a reception terminal (for example, 9G).

The transmission filter 109 and the reception filter 111 are each composed of, for example, a ladder type SAW resonator filter in which a plurality of SAW resonators 5 are connected in a ladder type. For example, the transmission filter 109 includes a plurality of (or even one) SAW resonators 5 (so-called series resonators) connected in series between the transmission terminal 9K and the antenna terminal 9C, and a line and a reference potential thereof. It has a plurality of (or even one) SAW resonators 5 (so-called parallel resonators) that connect the two.

Although not particularly shown, the transmission filter 109 and / or the reception filter 111 may be a filter other than the ladder type filter. For example, these filters may be a vertically coupled multiple mode (assuming to include a dual mode) type SAW resonator filter. In this multimode filter, for example, a plurality of IDT electrodes 23 are arranged adjacent to each other in the propagation direction of SAW, and a pair of reflectors 25 are provided on both sides thereof.

<Communication device>
FIG. 10 is a block diagram showing a main part of the communication device 151 as a usage example of the SAW device 1 (branch filter). The communication device 151 performs wireless communication using radio waves, and includes the SAW device 1.

In the communication device 151, the transmission information signal TIS including the information to be transmitted is modulated and the frequency is raised (conversion of the carrier frequency to a high frequency signal) by the RF-IC (Radio Frequency Integrated Circuit) 153, and becomes the transmission signal TS. Will be done. The transmission signal TS has unnecessary components other than the pass band for transmission removed by the bandpass filter 155, amplified by the amplifier 157, and input to the SAW device 1 (transmission terminal 9K). Then, the SAW device 1 removes unnecessary components other than the passing band for transmission from the input transmission signal TS, and outputs the removed transmission signal TS from the antenna terminal 9C to the antenna 159. The antenna 159 converts the input electric signal (transmission signal TS) into a radio signal (radio wave) and transmits the radio signal (radio wave).

Further, in the communication device 151, the radio signal (radio wave) received by the antenna 159 is converted into an electric signal (received signal RS) by the antenna 159 and input to the SAW device 1 (antenna terminal 9C). The SAW device 1 removes unnecessary components other than the reception pass band from the input received signal RS and outputs the signal to the amplifier 161. The output received signal RS is amplified by the amplifier 161 and the bandpass filter 163 removes unnecessary components other than the passing band for reception. Then, the frequency of the received signal RS is lowered and demodulated by the RF-IC153 to obtain the received information signal RIS.

The transmission information signal TIS and the reception information signal RIS may be low frequency signals (baseband signals) including appropriate information, and are, for example, analog audio signals or digitized audio signals. The passing band of the radio signal may conform to various standards. The modulation method may be phase modulation, amplitude modulation, frequency modulation, or a combination of any two or more of these. Although the direct conversion method is illustrated in FIG. 10, the circuit method may be any other appropriate method, for example, a double super heterodyne method. Further, FIG. 10 schematically shows only the main part, and a low-pass filter, an isolator, or the like may be added at an appropriate position, or the position of the amplifier or the like may be changed.

<Examples and Comparative Examples>
The SAW apparatus according to the examples and comparative examples was prototyped and its characteristics were investigated. The results are shown below.

11 (a) and 11 (b) are diagrams showing changes in characteristics due to temperature changes in the SAW apparatus according to Examples and Comparative Examples. FIG. 11A shows the results when the ambient temperature of the SAW apparatus was changed from −25 ° C. to 85 ° C. FIG. 11B shows the results when the ambient temperature of the SAW apparatus was changed from 25 ° C. to 85 ° C.

“E1” on the horizontal axis corresponds to the embodiment, and “C1” to “C3” on the horizontal axis correspond to the comparative example. Specifically, in Example E1, the reinforcing layer has a bus conductor 55 and a strip conductor 57. The detailed shape of the reinforcing layer of Example E1 is similar to that of FIG. 7 (second embodiment). In Comparative Example C1, a solid reinforcing layer is provided on the upper surface of the cover 7. Comparative Example C2 is not provided with a reinforcing layer. Comparative Example C3 is not provided with the reinforcing layer and the insulating layer covering the reinforcing layer (see 47 in FIG. 4, which is provided in the examples and other comparative examples).

The vertical axis shows the amount of change in frequency df (Hz) or the stress σ (Pa) generated in the piezoelectric substrate 13 when the ambient temperature of the SAW device 1 is changed. The change amount df is the change amount of the frequency at which the attenuation amount is 20 dB in the ladder type filter included in the SAW device 1. The amount of change df is obtained by actual measurement. The stress σ is obtained by simulation calculation.

The line L1 shows the stress σ. The lines L2 to L4 show the amount of change df, and various specific design values and / or the thickness of the reinforcing layer are different from each other.

From these figures, by forming the reinforcing layer 11 (E1) by the bus conductor 55 and the strip conductor 57, the amount of change df is smaller than that in the case where the solid reinforcing layer (C1) is provided. Can be confirmed. That is, it can be confirmed that the temperature compensation effect of the support substrate 15 can be suppressed from being reduced by the reinforcing layer. In other words, according to this configuration, the temperature compensation effect of the support substrate 15 can be maintained even if the reinforcing layer 11 is present. Further, it can be confirmed from the comparison of Comparative Examples C1 to C3 and Example E1 that the degree of the effect is sufficiently large. Further, the tendency of the improvement of the change amount df is similar to the tendency of the change of the stress σ, and it can be confirmed that the improvement of the change amount df is caused by the stress σ.

In Comparative Examples C2 and C3, although the amount of change df can be expected to be improved, it was confirmed that the lid portion 19 is deformed toward the space 21 due to external stress and comes into contact with the piezoelectric substrate 13. When actually mounted on the circuit board and molded by the transfer molding method, the space 21 was maintained in Comparative Example C1 and Example E1, but in Comparative Examples C2 and C3, the space 21 was crushed. confirmed.

The SAW device 1 manufactured by changing the ratio of the area of the reinforcing layer 11 to the area surrounded by the outer periphery of the frame portion 17 is mounted on the circuit board and molded by the transfer mold method to form the shape of the space 21. confirmed. As a result, as in the SAW device 201 shown in FIG. 7, when the bus conductor 55 is reduced and the ratio of the area of the reinforcing layer 11 to the area surrounded by the outer periphery of the frame portion 17 is 35%. , It was confirmed that the space 21 can be maintained.

FIG. 12 is a diagram showing changes in characteristics due to temperature changes in the SAW apparatus according to the other examples and comparative examples.

“E11” to “E13” on the horizontal axis correspond to the examples, and “C11” on the horizontal axis corresponds to the comparative example. Specifically, in Example E11, the detailed shape of the reinforcing layer is substantially the same as that of the reinforcing layer 11 of the first embodiment (FIG. 5). In Example E12, the detailed shape of the reinforcing layer is substantially the same as that of the reinforcing layer 211 of the second embodiment (FIG. 7). In Example E13, the detailed shape of the reinforcing layer is substantially the same as that of the reinforcing layer 311 of the third embodiment (FIG. 8). In Comparative Example C1, a solid reinforcing layer is provided on the upper surface of the cover 7.

Similar to FIG. 11, the vertical axis shows the amount of change in frequency df or the stress σ generated in the piezoelectric substrate 13 when the ambient temperature of the SAW device 1 is changed. Also in this figure, the amount of change df is obtained by actual measurement, and the stress σ is obtained by simulation calculation.

The bar graph shows the amount of change df depending on the position of the top. The diamond-shaped plot shows the stress σ.

From this figure, it was confirmed that in each of Examples E11 to E13, the effect of reducing the amount of change df was obtained as compared with Comparative Example C11, and that this effect was obtained by reducing the thermal stress. it can. Further, from the comparison of Examples E11 and E13, it can be confirmed that the change amount df becomes smaller when the number of strip conductors 57B extending in the propagation direction of SAW is relatively small. From the viewpoint of reducing the amount of change df, Example E12 is the best. However, this is not always the case from the viewpoint of reinforcing the cover 7.

The present invention is not limited to the above embodiments, and may be implemented in various embodiments.

The elastic wave device is not limited to the SAW device. For example, the elastic wave device may be a BAW (Bulk Acoustic Wave) device or may include a piezoelectric thin film resonator. Further, the elastic wave device is not limited to a demultiplexer (duplexer in a narrow sense) having a transmission filter and a reception filter, and may be, for example, a demultiplexer that demultiplexes a plurality of received signals. Further, the elastic wave device may be one that demultiplexes three or more signals, or may have three or more filters.

The elastic wave device may not have a through conductor 45 penetrating the cover and a terminal 9 on the cover. For example, a through hole may be provided on the pad 43 of the cover, and the pad of the circuit board on which the elastic wave device is mounted and the pad 43 may be directly joined by bumps.

The bus conductor and the strip conductor may be inclined with respect to the propagation direction of the elastic wave. Bus conductors and strip conductors do not have to extend at a constant width and may vary in width continuously or stepwise. Further, the bus conductor and the strip conductor do not have to extend linearly, and may extend so as to be curved or bent. A bus conductor wider than the strip conductor may not be provided. Further, the strip conductor may be relatively wide. For example, the strip conductor may have a width comparable to that of the bus conductor of the embodiment.

From this disclosure, it is possible to extract a technique that does not presuppose the existence of a support substrate. For example, the following techniques can be extracted.

Piezoelectric board and
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
With the bus conductor extending on the cover,
On the cover, a first strip conductor extending from the bus conductor with a width narrower than that of the bus conductor and at least partially overlapping the space in plan perspective.
Has an elastic wave device.

Piezoelectric board and
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
A plurality of first strip conductors extending on the cover and at least partially overlapping the space in planar fluoroscopy.
One or more second strip conductors intersecting the plurality of first strip conductors,
Have and
An elastic wave device in which the number of one or more second strip conductors is less than half the number of the plurality of first strip conductors.

Piezoelectric board and
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
A plurality of first strip conductors extending on the cover and at least partially overlapping the space in planar fluoroscopy.
Have and
The plurality of first strip conductors are elastic wave devices having a thickness larger than a width.

Further, from the present disclosure, it is possible to extract not only a support substrate but also a technique that does not presuppose the existence of a strip conductor. For example, the following techniques can be extracted.

Piezoelectric board and
The excitation electrode located on the piezoelectric substrate and
The cover covering the excitation electrode and
A first through conductor that is electrically connected to the excitation electrode and penetrates at least the upper surface side portion of the cover.
A terminal located on the cover and away from the first through conductor in a plan view.
A conductor layer located on the cover and connecting the first through conductor and the terminal,
Have and
The conductor layer is an elastic wave device having a first extending portion and a second extending portion extending in a direction intersecting each other with the terminal as a starting point.

In the above technique, the cover may not form a space on the excitation electrode. Therefore, the elastic wave device may be an elastic boundary wave device (however, it is included in the SAW device in a broad sense).

Further, in the above example, the case where the frame portion 17 constituting the cover 7 is located on the piezoelectric substrate 13 has been described as an example, but the present invention is not limited to this. Specifically, the piezoelectric substrate 13 may be positioned inside the support substrate 15 in a plan view, and the frame portion 17 may be positioned on the support substrate 15 not covered by the piezoelectric substrate 13. In the above example, the temperature compensation effect of the support substrate 15 is effectively exhibited by suppressing the tensile stress applied to the piezoelectric substrate. On the other hand, when the frame portion 17 is positioned on the support substrate 15, the tensile stress applied to the support substrate 15 can be reduced as compared with the case where the conductor pattern is a solid pattern. As a result, the thermal expansion of the piezoelectric substrate 13 can be effectively suppressed.

1 ... SAW device (surface acoustic wave device), 7 ... cover, 13 ... piezoelectric substrate, 15 ... support substrate, 23 ... IDT electrode (excitation electrode), 55 (55A and 55B) ... strip conductor.

Claims (15)

Piezoelectric board and
A support substrate located on the lower surface of the piezoelectric substrate and having a coefficient of thermal expansion smaller than that of the piezoelectric substrate.
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
A plurality of first strip conductors extending in parallel with each other on the cover and at least partially overlapping the space in planar fluoroscopy.
A first bus conductor extending on the cover with a width wider than that of each of the plurality of first strip conductors.
Have and
The plurality of first strip conductors extend from the first bus conductor.
Elastic wave device. It further has a second bus conductor extending in parallel with the first bus conductor and wider than the plurality of first strip conductors.
The elastic wave device according to claim 1 , wherein the plurality of first strip conductors are bridged between the first bus conductor and the second bus conductor. Piezoelectric board and
A support substrate located on the lower surface of the piezoelectric substrate and having a coefficient of thermal expansion smaller than that of the piezoelectric substrate.
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
A plurality of first strip conductors extending in parallel with each other on the cover and at least partially overlapping the space in planar fluoroscopy.
One or more second strip conductors intersecting the plurality of first strip conductors ,
A has,
The number of one or more second strip conductors is less than half the number of the plurality of first strip conductors.
Elastic wave device. The excitation electrode is an IDT electrode having a plurality of electrode fingers extending in parallel with each other.
The elastic wave device according to claim 3 , wherein the plurality of first strip conductors extend in a direction in which the plurality of electrode fingers extend. The elastic wave device according to claim 3 or 4 , wherein the one or more second strip conductors do not overlap with the plurality of electrode fingers in planar fluoroscopy. Piezoelectric board and
A support substrate located on the lower surface of the piezoelectric substrate and having a coefficient of thermal expansion smaller than that of the piezoelectric substrate.
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
A plurality of first strip conductors extending in parallel with each other on the cover and at least partially overlapping the space in planar fluoroscopy.
Have and
The plurality of first strip conductors are larger in thickness than width.
Elastic wave device. The invention according to any one of claims 1 to 6 , wherein at least a part thereof is located in the cover and further has a connecting conductor connecting the excitation electrode and the plurality of first strip conductors. Elastic wave device. Piezoelectric board and
A support substrate located on the lower surface of the piezoelectric substrate and having a coefficient of thermal expansion smaller than that of the piezoelectric substrate.
The excitation electrode located on the piezoelectric substrate and
A cover forming a space on the excitation electrode and
A plurality of first strip conductors extending in parallel with each other on the cover and at least partially overlapping the space in planar fluoroscopy.
A first through conductor that is electrically connected to the excitation electrode and penetrates at least the upper surface side portion of the cover.
A terminal located on the cover and away from the first through conductor in a plan view.
A conductor layer located on the cover and connecting the first through conductor and the terminal,
Have and
The conductor layer has a first extending portion and a second extending portion extending in a direction intersecting each other with the terminal as a starting point.
Elastic wave device. The elastic wave device according to claim 8 , wherein the conductor layer further has a third extension portion extending in parallel with the first extension portion and connected to the second extension portion. The elastic wave device according to claim 9 , wherein the conductor layer further has a fourth extension portion bridged between the first extension portion and the third extension portion. The plurality of first strip conductors extend from the first extension portion in a direction intersecting the first extension portion, and are narrower than the first extension portion and the second extension portion. Item 2. The elastic wave device according to any one of Items 8 to 10 . Said plurality of first strip conductors, the first extending portion are bridged between the third extending portion, the first to width than the third extended portion is narrow claim 9 or 10. The elastic wave device according to 10 . A second penetrating conductor that penetrates only the lower surface side portion of the cover,
An internal wiring embedded in the cover and extending parallel to the upper surface of the piezoelectric substrate from the second through conductor.
Has more
The elastic wave device according to any one of claims 8 to 12 , wherein the first through conductor penetrates only the upper surface side portion of the cover and is connected to the internal wiring. A transmission filter that filters the transmission signal and outputs it to the antenna,
A reception filter that filters the reception signal from the antenna,
Have and
A demultiplexer in which at least a part of the transmission filter and the reception filter is included in the elastic wave apparatus according to any one of claims 1 to 13 . With the antenna
The demultiplexer according to claim 14 , which is connected to the antenna,
The IC connected to the demultiplexer and
Communication equipment that has.

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